{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2038-3KB40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2038-3KB40","canonicalUrl":"https://aoctrl.com/siemens/3RT2038-3KB40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2038-3KB40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS Size S2 coupling contactor, 3RT2038-3KB40, 24 VDC coil, spring-cage terminals, 55 mm wide, 130 mm deep, DIN-rail snap-on mounting.","salesMarkdown":"## Coupling contactor, Size S2 — 24 V coil, spring-cage terminals The 3RT2038-3KB40 is a Siemens SIRIUS Size S2 coupling contactor. It carries a 24 V rated coil with a 10 A switching capacity at that voltage. The contactor uses spring-cage terminals on the main contacts, accepting 2x (0.5... 2.5 mm²) solid or stranded wire. ## Switching performance and mechanical life The AC-1 resistive load curve supports up to 700 ops/h. Mechanical life typical is 10,000,000 operations. Arcing time runs 10...20 ms; DC switching times are 30...55 ms. Auxiliary switch block is included. The contactor carries a 1.2 full-scale factor and 0.8 initial value — derate accordingly for inductive loads.","metaTitle":"Siemens 3RT2038-3KB40 SIRIUS coupling contactor, 24 V coil,","metaDescription":"Siemens 3RT2038-3KB40 SIRIUS coupling contactor, Size S2, 24 VDC coil, 10 A switching, spring-cage terminals. 55 mm wide, 130 mm deep. DIN-rail mount. Current lifecycle stage. Sour","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"130 mm","Width":"55 mm","at DC":"30 ... 55 ms","Height":"114 mm","Upwards":"10 mm","Forwards":"10 mm","Downwards":"10 mm","Arcing Time":"10 ... 20 ms","At The Side":"6 mm","Rated Value":"24 V","Initial Value":"0.8","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Spring-type terminals","at AC-1 maximum":"700 1/h","at AC-2 maximum":"350 1/h","at AC-3 maximum":"500 1/h","at AC-4 maximum":"150 1/h","lifecycle_stage":"current","Auxiliary Switch":"Yes","During Operation":"-25 ... +60 °C","Fastening Method":"screw and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715","Full-Scale Value":"1.2","at AC-3e maximum":"500 1/h","For Main Contacts":"18 ... 1","Mounting Position":"+/-180° rotation possible on vertical mounting surface; can be tilted forward and backward by +/- 22.5° on vertical mounting surface","Size Of Contactor":"S2","Solid Or Stranded":"2x (0.5 ... 2.5 mm²)","Product Brand Name":"SIRIUS","Inrush Current Peak":"2.6 A","Product Designation":"Coupling contactor","at 24 V rated value":"10 A","at 48 V rated value":"2 A","at 60 V rated value":"2 A","Of Contactor Typical":"10 000 000","at 110 V rated value":"1 A","at 125 V rated value":"0.9 A","at 220 V rated value":"0.3 A","at 230 V rated value":"15 hp","at 400 V rated value":"3 A","at 440 V rated value":"0.6 A","at 480 V rated value":"65 A","at 500 V rated value":"2 A","at 600 V rated value":"62 A","at 690 V rated value":"1 A","Side-By-Side Mounting":"Yes","For Auxiliary Contacts":"20 ... 14","For Main Current Circuit":"screw-type terminals","at 110/120 V rated value":"5 hp","at 200/208 V rated value":"20 hp","at 220/230 V rated value":"25 hp","at 460/480 V rated value":"50 hp","at 575/600 V rated value":"60 hp","Locked-Rotor Current Peak":"2.1 A","Relative Humidity Minimum":"10 %","Holding Current Mean Value":"40 mA","Of Main Circuit Rated Value":"6 kV","at AC-3 rated value maximum":"690 V","at AC in hot operating state":"17.1 W","at AC-2 at 400 V rated value":"37 kW","at AC-3e rated value maximum":"690 V","at AC-4 at 400 V rated value":"55 A","safety-related switching OFF":"Yes","Substance Prohibitance (Date)":"10/01/2014","Design Of The Surge Suppressor":"with varistor","Duration Of Inrush Current Peak":"50 µs","Locked-Rotor Current Mean Value":"0.9 A","Duration Of Locked-Rotor Current":"230 ms","Of Auxiliary Circuit Rated Value":"6 kV","at AC-5a up to 690 V rated value":"79.2 A","at AC-5b up to 400 V rated value":"66.4 A","For Auxiliary And Control Circuit":"spring-loaded terminals","Function Module For Communication":"No","With Type Of Assignment 2 Required":"gG: 160A (690V,100kA), aM: 80A (690V,100kA), BS88: 125A (415V,80kA)","Without Load Current Share Typical":"1 W","closing power of magnet coil at DC":"21.5 W","holding power of magnet coil at DC":"1 W","At Contactor For Auxiliary Contacts":"Spring-type terminals","With Type Of Coordination 1 Required":"gG: 250 A (690 V, 100 kA), aM: 160 A (690 V, 100 kA), BS88: 200 A (415 V, 80 kA)","operational current at AC-12 maximum":"10 A","at AC in hot operating state per pole":"5.7 W","for AWG cables for auxiliary contacts":"2x (20 ... 14)","number of NO contacts for main contacts":"3","reference code according to IEC 81346-2":"Q","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²)","Number Of Poles For Main Current Circuit":"3","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","mirror contact according to IEC 60947-4-1":"Yes","with low demand rate according to SN 31920":"40 %","Finely Stranded Without Core End Processing":"2x (0.5 ... 2.5 mm²)","with high demand rate according to SN 31920":"73 %","Type Of Voltage Of The Control Supply Voltage":"DC","Limited To 1 S Switching At Zero Current Maximum":"1 298 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 5 S Switching At Zero Current Maximum":"898 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 10 S Switching At Zero Current Maximum":"640 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 30 S Switching At Zero Current Maximum":"414 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 60 S Switching At Zero Current Maximum":"333 A; Use minimum cross-section acc. to AC-1 rated value","contact rating of auxiliary contacts according to UL":"A600 / P600","Of Main Circuit With Degree Of Pollution 3 Rated Value":"690 V","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","Of Auxiliary Circuit With Degree Of Pollution 3 Rated Value":"690 V","For Short-Circuit Protection Of The Auxiliary Switch Required":"gG: 10 A (500 V, 1 kA)","minimum cross-section in main circuit at maximum AC-1 rated value":"35 mm²","number of NC contacts for auxiliary contacts instantaneous contact":"1","number of NO contacts for auxiliary contacts instantaneous contact":"1","Of The Contactor With Added Electronically Optimized Auxiliary Switch Block Typical":"5 000 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=578170&mlfb=3RT2038-3KB40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2038-3KB40/alternatives.json"},"ai":{"faq":[{"question":"What are the key dimensions of 3RT2038-3KB40?","answer":"Width is 55 mm, height is 114 mm, depth is 130 mm. It mounts on 35 mm DIN rail per DIN EN 60715."},{"question":"What type of coil and terminals does this contactor use?","answer":"The coil is rated 24 V with a 10 A switching capacity at that voltage. Main contacts use spring-cage terminals accepting 2x (0.5 to 2.5 mm²) solid or stranded wire."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2038-3KB40","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/siemens/3RT2038-3KB40 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}